Electrical erosion micro hole drilling of aerospace materials

High production standards are required in the aviation industry. One of these requirements is the dimentional accurancy and surface quality of the manufactured parts. Electrical Discharge Machining (EDM) is one of the precise production method in the non-traditional manufacturing methods. Micro hole-EDM is widely preferred for drilling high aspect ratio holes. In this study, Micro hole-EDM process was investigated and its effects on the aerospace materials were examined. These materials were selected as Nickel alloy Inconel 718 and Titanium alloy Ti-6Al-4V. The EDM parameters were selected as; discharge current (I), pulse on time (Ton) and pulse off time (Toff). The Output parameters were selected as; material removal rate (MRR), surface roughness value (Ra) and electrode wear rate (EWR). Design of Experiment (DOE) was created by the Taguchi method. The results were transformed into a mathematical model with regression analysis, and the relationship between input parameters and response parameters was interpreted through this model. Reliability of the model was analyzed by analysis of variance. With regression analysis optimization, it is aimed to reach the optimum values of MRR, EWR and Ra. Validity of the results was supported by validation experiments.